1. Field
Aspects of the present invention relate to a battery module.
2. Description of the Related Technology
A rechargeable lithium ion secondary battery may be used, for example, in a small-sized electronic device, such as a notebook computer or a cellular phone. Also, because recently developed rechargeable lithium ion secondary batteries have advantageous characteristics, including high output power, high capacity, and lightness in weight, as compared to other types of rechargeable secondary batteries, they are widely used in hybrid vehicles or electric vehicles.
Since a lithium ion secondary battery used in a hybrid vehicle or an electric vehicle has a relatively high capacity, it is important to provide a safety device against overcharge or puncture. The safety device should rapidly cut off a charge or discharge path when the lithium ion secondary battery is overcharged or punctured.